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Homework Help: Partial Pressure problem with three tanks, only [atm] and [L] are given. H2, N2, CO2

  1. Mar 22, 2006 #1
    Temperature is constant.

    At first, this system is closed.

    In tank one:

    A 2 Liter tank containing H2 at a pressure of 1.5 atmospheres.

    In tank two:

    A 1 Liter tank containing N2 at a pressure of 3 atmospheres.

    In tank three:

    A 4 Liter tank containing CO2 at a pressure of 1 atmosphere. Also, a non-volatile liquid covers the bottom 1.67 Liters.

    The system is then opened. What is the TOTAL PRESSURE in the opened system, and the PARTIAL PRESSURE of each gas?

    I would think that the problem gives the partial pressures already, right?

    So partial of H2 = 1.5 atm, N2 = 3 atm and CO2 = 1 atm

    And just add all the pressures together to get 5.5 atm as the total pressure?

    Is this right?
  2. jcsd
  3. Mar 23, 2006 #2


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    Vinny Cee, I don't understand the question. By "system is opened", do you mean that the system is opened to the atmosphere? Or do you mean that the three tanks are opened and allowed to mix?
  4. Mar 23, 2006 #3
    I'm assuming the tanks are opened and allowed to mix, in which case you're answer is incorrect, VinnyCee.


    I believe you have to use the P1V1 = P2V2 and solve for P2 for each of the three tanks (using the total volume as V2) and then figure things out from there. However, I don't know exactly what to do with the third tank and its non-volatile liquid. Unless, you simply use the volume of 2.33 L instead of 4 L. According to my assumption, the total pressure would end up being 1.56 atm. and the partial pressures would be .563, .563, and .437.

    I'll let someone else take this one =).
    Last edited: Mar 23, 2006
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